FIG. 1. illustrates a typical ultrasound system 10. An ultrasound transducer 12 is coupled to its associated ultrasound console 14 via a cable 16, which is routed into an ultrasound transducer connector assembly 18. Ultrasound transducer connector assembly 18 mates with a corresponding receptacle 20 located on ultrasound console 14. Ultrasound console 14 and ultrasound transducer 12 exchange electrical signals via cable 16.
FIG. 2 offers a more detailed representation of ultrasound transducer connector assembly 18, and shows an electrical circuit 30 and an electrical connector 22 enclosed within a connector housing 24. Electrical connector 22 may have as many as 500 contacts (not shown). To protect the integrity of the electrical signals, a radio frequency interference (RFI) shield 26 is disposed about electrical circuit 30 and coupled to coaxial (coax) shield 28. In the prior art, electrical connector 22 is a zero insertion force (ZIF) connector.
FIG. 3 illustrates a generic ZIF connector 110. It includes a movable connector component 112 with movable electrical contacts 114, designed to mate with a stationary connector component 116 having stationary electrical contacts 118.
For mating, movable connector component 112 is brought towards stationary connector component 116 in the direction indicated by arrow 120. Initially, there is a gap 122 separating movable electrical contact 114 from stationary electrical contact 118, so that the contacts are not subjected to any friction or insertion force. A locking mechanism 124 traverses movable connector component 112 through an aperture 126 and is received in a recess 128 of stationary connector component 116. Locking mechanism 124 is rotated, as indicated by arrow 130, causing movable connector component 112 to close in the direction of arrow 132. This reduces gap 122 allowing movable electrical contact 114 to wipe against stationary electrical contact 118 to make an electrical connection.
ZIF connectors minimize the physical stress exerted upon their electrical contacts, thus avoiding wear and potential damage to the contacts. However, these connectors are mechanically more complex, larger and more expensive than simpler connectors.
Although ZIF locking mechanism 124 offers some latching capability to help secure movable connector component 112 with stationary connector component 116, this latching alone is not sufficient to secure the mating of a typical ultrasound transducer connector assembly to its ultrasound console. Accordingly, ultrasound transducer connectors usually include a latching mechanism in addition to the incidental latching offered by the ZIF connector.
FIG. 4 illustrates a prior art ultrasound transducer connector assembly 150 with a 1/4 turn latching mechanism comprising a handle 152 and a shaft 154. Shaft 154 traverses an outer shell 156, and has an end 158 that guides ultrasound transducer connector assembly 150 into a mating connector assembly (not shown). The connection is secured by rotating handle 152 to lock ultrasound transducer connector assembly 150 into its mate. The 1/4 turn latching mechanism is mechanically more complex, larger and more expensive than simpler latching mechanisms.
RFI shielding is provided by some form of electrically conductive barrier disposed about the electrical circuit for which protection is desired. The prior art generally provides RFI shielding by enclosing the circuitry within a connector housing comprised of either a metal outer shell or a metal inner shell surrounded by a plastic outer shell. For example, referring again to FIG. 4, the prior art connector assembly 150 includes outer shell 156 made of metal.
When components such as these are manufactured, their physical dimensions must be held to fairly strict tolerances to ensure proper fit during assembly. Additionally, metal is generally more expensive than plastic. Therefore, the cost of an ultrasound transducer connector assembly can be reduced by minimizing the use of components with strict manufacturing tolerances, and by using plastic rather than metal where possible.
Accordingly, there is a need for an ultrasound transducer connector assembly with an electrical connector of minimal mechanical complexity, size and cost, and a latching mechanism of minimal mechanical complexity, size and cost. There is a further need for an ultrasound transducer connector assembly with an RFI shield and connector housing minimizing the use of components requiring strict manufacturing tolerances and minimizing the use of metal components.